Forage Accumulation and Nutritive Value of Italian Ryegrass–Kura Clover Mixture in Central Europe

The quest to reduce importation of plant protein for livestock feed and to reduce expense and environmental consequences of nitrogen fertilizer use have resulted in renewed interest in forage legumes in EU countries. The objectives of this study were: (i) to assess forage accumulation and nutritive value of mixtures of Italian ryegrass (IRG, Lolium multiflorum Lam.) and kura clover (KC, Trifolium ambiguum M. Bieb.), and (ii) to model milk production potential of this mixture, relative to IRG and KC monocultures in northern Poland. Italian ryegrass and KC were grown in monocultures or intercropped (IRG‐KC mixture) and harvested three times per year in two consecutive years. Italian ryegrass had greatest accumulated forage in harvest 1 and 2, followed by IRG‐KC and the KC monoculture. In harvest 3, IRG‐KC accumulated more forage than KC or IRG. Crude protein, neutral detergent fiber digestibility, and in vitro true digestibility across harvests followed the trend KC > IRG‐KC > IRG. The KC monoculture had the greatest calculated milk per megagram dry matter but the least milk per hectare, whereas IRG monoculture had least milk per megagram dry matter and greatest milk per hectare, with intermediate values for the IRG‐KC mix. Although forage accumulation of the mixture was less than that of nitrogen fertilized IRG, greater crude protein concentration and no nitrogen fertilizer application make it an intriguing opportunity for EU countries striving to reduce feed protein imports and use of fertilizer nitrogen.